w23qp1222

Red, green and violet lights are part of the visible spectrum of light. What is the order of colours from shortest to longest wavelength?

• red → green → violet

• red → violet → green

• violet → red → green

• violet → green → red

• in a vacuum

• in diamond

• in glass

• in water

Which graph of current I against time t represents an alternating current (a.c.)?

• 
• 
• 
• 

What is the effect on the wire?

• The force on the wire alternates between one direction and the opposite direction.

• The force on the wire is constant in size and direction.

• There is no force acting on the wire at any time.

• There is only a force on the wire when the current reverses.

A transformer has Np turns on its primary coil and Ns turns on its secondary coil. The voltage across the primary coil is Vp and the voltage across the secondary coil is Vs.

What is the relationship between these four quantities?

• 
• 
• 
• 

Which diagram shows a negatively charged ion?

• Diagram A

• Diagram B

• Diagram C

• Diagram D

What is the most effective precaution to reduce the risk when handling, storing or using a radioactive source that emits γ-rays?

• Handle the source for the least possible time.

• Have a fire extinguisher nearby when using the source.

• Store the source at a low temperature.

• Wear plastic safety goggles when handling the source.

The Sun transfers energy to the Earth through electromagnetic radiation.

What are two of the parts of the electromagnetic spectrum to which most of the energy belongs?

• gamma rays and X-rays

• infrared radiation and visible light

• microwaves and visible light

• radio waves and microwaves

The circuit diagram shows a circuit used to run a d.c. motor from an a.c. supply. Which graph shows the current in the motor?

• Graph A

• Graph B

• Graph C

• Graph D

• The new induced current is in the opposite direction and causes the soft iron to attract the N pole.

• The new induced current is in the opposite direction and causes the soft iron to repel the N pole.

• The new induced current is in the same direction and causes the soft iron to attract the N pole.

• The new induced current is in the same direction and causes the soft iron to repel the N pole.